Real Property is best understood when it is contrasted with personal property. I found this by wandering the internet:

William Blackstone, in his 1756-1759 Commentaries on the Laws of England (Volume 2), wrote:

"Things real are such as are permanent, fixed and immovable; which cannot be carried out of their place, as lands and tenements.

"Things personal are goods, money and all other moveable; which may attend the owner's person wherever he thinks proper to go."